The latest from the MySQL community

Are you a brand-newbie to MySQL? Coming from another database (or databases)? If so, here are some concepts to read up on right away to ease your confusion down the road. These are the top things I wish someone had told me about before I did anything else with MySQL.

(I’ve had a lot of questions along these lines, and have posted on all of each of these items somewhere, but thought it’d be more helpful to gather the points together into one place.)

MY TOP 2 “BEFORE YOU BEGIN” TOPICS

#1: storage engines. Before you do any big planning, if you don’t know what a “storage engine” is, find out!
I can’t think of a good analogy for what a storage engine is. The best I can come up with is, you know how with Oracle you choose your index types (btree? bitmap? etc)? In MySQL, you choose your table types (and with them, the index types). Your choice determines a lot. Each storage engine (table …

Due to some discrepancies between the Eclipse 3.2.2 compiler and Sun's javac we needed to upgrade our development environments to Eclipse 3.3. Otherwise we could not tell for sure that something that looked ok in Eclipse would compile in the daily build process.

Even though I had used 3.3 privately for some time now, there is always some tension when switching a whole bunch of developers in a really large project.

At first everything seemed fine, apart from some minor issues that could be easily worked around.

However I ran into a nasty little bug regarding the CVS integration when I had to switch a workspace that had been checked out on HEAD to another branch. That branch had been created to keep the Helpers- and Utilities-Refactoring I wrote about before separate from the HEAD until it is complete.

As I sit in the lobby, taking a break, waiting to leave to the airport for my next destination, I just think about what a great week I’ve had. Its been packed, with just far too much to do. Mornings starting at 4.30am and nights ending at 3am just seem so normal. I’ve taken a ridiculous number of photos, which I hope will make their way online slowly, but expect to see them even in the following month.

At the team exhibitions…

One of the great things about the Heidelberg DevMeeting was being able to interact with my team a lot. Being in a distributed environment, I must say this is the most face-to-face time we’ve had just to hang out, talk, eat, get stuff done, drink, walk around, socialise, etc. Its highly amazing. Really. Don’t even think about doing so at the …

I'm really grateful to Zack Urlocker for his post today on how MySQL competes against Google et al in the hiring department. More importantly (for me), he discusses how MySQL closes the distance its employees may feel while working in a highly distributed company:

So that means that they don't have to commute, they don't have to hang out in boring HR meetings, they can just focus on what they like, which is coding. We may not have all the perks offered by big companies, but at the end of the day, developers know they are working on something important and they can do it from their home rather than relocating to Silicon Valley....

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If you're a private open source company, how do you compete against the likes of Google or VMWare for talent? At MySQL, we've found that one of the most attractive elements of the company is the fact that we are globally distributed. We have over 300 employees in nearly 30 countries. (That's in total, not 300 in each!) And over 70% of employees work from home. Among developers, the rate is over 90%. So that means that they don't have to commute, they don't have to hang out in boring HR meetings, they can just focus on what they like,... READ MORE

I was glad to have the opportunity to join the MySQL developers in Heidelberg for a few days, so thanks to MySQL for the invitation. In between great food, quite a few beers and a number of boat trips we managed to get a significant amount of work done!

In what could be considered a follow-up to the engine summit at Google following the MySQL User's conference, I joined Calvin Sun, Brian Aker, Jeffrey Pugh, Monty and others from MySQL and the engine developing community to discuss things concerning storage engines.

One of the main topics of the meeting was features and other changes to the MySQL front-end as required by the engines. Some of the requirements (such as an interface to the MySQL optimizer) would really …

After almost eight months of waiting, I am finally allowed to publish my thesis paper:

Design and Implementation of a Workflow Engine
This thesis discusses the design and implementation of a software component that faciliates the specification, management, and execution of so-called workflows. The discussion of this component's design includes the semantics and syntax of the underlying workflow model as well as the actual software design. The former builds upon the Workflow Patterns [BK03] terminology, the latter on the concepts of a Workflow Virtual Machine [SF04] and the idea that a workflow system should be comprised of loosely coupled components [DAM01, DG95, PM99].

The thesis paper is published under the Creative Commons Attribution 2.0 Germany license, the software that has been developed as part of this thesis has been released under the New BSD License as part of …

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Sometimes, you forget simple concepts when your head is deep into the waters of solving other problems.

I dealt with a problem this weekend that was the result of code I wrote that we use for regression testing. The code is designed with a fairly simple concept: run all of our feeds and take the output of how Grazr Feed Server code parses (that the website/widget sees), store into MySQL the md5_hex of the OPML and JSON in a table for a known good version. Then, you update the code to the new test version, create a table with the same schema as the results for the known good version, run the regression again with the new code. When the regression for the new code is completed, then you compare the two tables.

The problem that I encountered was that I was performing a join against records that only existed for both data sets. Say for instance, I run regression for the known good version and produce 30,000 records. Then I …